December 13, 2010

Blogger challenges my post on sex offender risk assessment

My report on a promising new method for assessing sex offender recidivism risk prompted a reaction from Robin Wilson over at a new blog by the publishers of Sexual Abuse, the journal of the Association for the Treatment of Sexual Abusers (ATSA).

My interest dissolved into disappointment when I realized that the response sidestepped substantive discussion of the new research, a collaborative project by scholars in the United States, New Zealand, and Australia finding that accuracy of risk prediction can be enhanced by using age-stratified tables.

Instead of engaging with the scientific merits of this study, Dr. Wilson focused on the Static-99 actuarial tool, chastising me for being overly critical of that approach:

Dr. Franklin has something of a penchant for the flamboyant. Actually, I often appreciate a bit of bluster, but I think we also need to avoid bias and unnecessary sideswipes at our colleagues. In the spirit of honesty, let me say that I work in a civil commitment center and that I am a certified trainer for the Static-99 group of measures. So, my potential bias is on the table.

Is having an opinion a form of bias?

The term bias refers to a partiality that interferes with the ability to be fair or objective. Expressing a point of view does not make one biased. Rather, the articulation of informed opinion advances professional practice. Indeed, such "expert opinion" is precisely what courts seek from forensic psychologists when they solicit our testimony. An expert witness is expected to have a firm grounding in the applicable science, and to be able to critically analyze its strengths and weaknesses as it applies to a specific issue or case.

It is that process of reflection -- invoking complementary theoretical perspectives from criminology, sociology, anthropology and international studies relevant to forensic psychology -- that germinates many an idea for this blog. I welcome critical engagement with these ideas, but hope that interlocutors can themselves refrain from diversionary ad hominem arguments.

Why pick on the Static-99?

Dr. Wilson's main theme is that I am unduly critical of the Static-99 and its developers.

The Static-99 website promotes the tool as "the most widely used sex offender risk assessment instrument in the world." As Dr. Wilson himself notes in another publication, its "prolific use in sexual offender civil commitment proceedings" is one reason it generates so much debate.

But Dr. Wilson is correct in pointing out that many of the Static-99's flaws apply equally to its cousins. In referencing the Static-99, I in no way intend to exempt other actuarials from critique. Indeed, in previous posts I have discussed problems with the MnSOST-R and have reported the results of studies on the relative accuracy of the Static-2002, Risk Matrix 2000, RRASOR and other actuarial tools.

Dr. Wilson makes an essential point in defense of the Static-99. By encouraging us to anchor our risk estimates in empirical data, he reminds us, actuarials serve as a counterbalance against clinicians' inherent tendency to vastly overestimate sex offender risk:

Maybe, what Dr. Franklin should be highlighting more is the fact that some evaluators are falling prey to partisan concerns. A well done sex offender risk assessment [using an actuarial instrument] should say the same thing, regardless of who you are working for.

In principle, Dr. Wilson is entirely correct. Sadly, from my vantage point as a forensic psychologist working in the courtroom trenches, I see endemic partisan allegiance in this arena. The Static-99 is being systematically deployed to provide a scientific veneer for highly questionable practices in the service of civil commitment.

The problem is not just a handful of rogue evaluators. The latest permutation of the Static-99 fosters such misuse. I am referring to the developers' advice to assign sex offenders to one of four categories with different levels of actuarial risk. As I pointed out in a previous post, this procedure introduces a large element of clinical judgment into a procedure whose very existence is predicated on doing away with such subjectivity. In the polarized Sexually Violent Predator arena, evaluators now have an easy way to elevate their estimate of an offender's risk by comparing the individual to the highest-risk group rather than to the lower recidivism figures for sex offenders overall. This practice reflects a tautology, or logical fallacy. In a civil commitment proceeding the evaluator essentially says: "This offender is high risk. Just look at the recidivism rates for offenders in the high-risk group to which I have assigned him."

The Static-99 developers may be quite well intentioned, as Dr. Wilson says. But subjective intent is far less important than real-life effects. The road to Hell, as they say, is paved with good intentions. I will not be alone in cheering when I hear that the Static-99 developers have stepped up and publicly condemned the systematic misuse of their instruments in courthouses all across the United States.

If Dr. Wilson's point was to chastise me for the use of the term reliability where I meant to say accuracy, I stand corrected. (I have made the correction to the original post.) However, I make no apologies for expressing an informed viewpoint and, indeed, I unflinchingly embrace such a role as part of my professional obligation. The goal of my blog is not to convince people that I have all the answers. Rather, I am happy if I encourage critical reflection and stimulate people to read the original source material. In so doing, I hope I am doing my part to advance science and combat bias.

The award-winning Texas blog Grits for Breakfast has a more favorable reaction, with links to additional topics of interest.

2 comments
:

Good for you Karen! Way to stand your ground and continue to expose the weaknesses and real risks in using the actuarials to predict what is unpredictable. The SVP laws are a thin veil for preventive detention. Anyone who disagrees with this truth is in my opinion kidding themselves or justifying their role in the 21st Century Witch Hunt.

"The problem is not just a handful of rogue evaluators. The latest permutation of the Static-99 fosters such misuse. I am referring to the developers' advice to assign sex offenders to one of four categories with different levels of actuarial risk. As I pointed out in a previous post, this procedure introduces a large element of clinical judgment into a procedure whose very existence is predicated on doing away with such subjectivity."

Agreed. The use of categorical risk tables is little more than a quick fix to address issues of variablity between groups on actuarial tools. The future of statistic-based risk assessment is to have a structure tool to evaluate dynamic risk along side of actuarial risk. Structured tools have been proven to be more accurate in decision making than raw clincial judgment (sorry, can't remember the reference), and having a standard of comparison to actuarial predictions SHOULD be able to account for the variability that the categorical tables attempts to address as well as change over time (for better or worse). Research in progress in Canada, the US, the UK, and other countries.

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Karen Franklin, Ph.D. is a forensic psychologist and adjunct professor at Alliant University in Northern California. She is a former criminal investigator and legal affairs reporter. See her website for more professional background. If you find this blog's content helpful, you may subscribe to its digest version (via "subscribe" box, above) to automatically receive new posts.

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